SIMULTANEOUS ANALYSIS OF MULTI-COMPONENTS IN KO-KENG-TANG PREPARATION BY HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

Abstract

To enhance the quality control of “Ko-Keng-Tang,” a simultaneous determination method on six marker substances including puerarin, daidzin, and daidzein (from Puerariae Radix), cinnamic acid (from Cinnamomi Ramulus), paeoniflorin (from Paeoniae Radix), and glycyrrhizin (from Glycyrrhizae Radix) was developed using high-performance liquid chromatography. Extracted samples were analyzed with a reverse-phase column (Inertsil 5 ODS-2, 4.6 I.D. × 250 mm.) at 30 °C and eluted ingredients with a mixture of 5%, 40%, and 90% acetonitrile (adjusted to pH 2.8 with phosphoric acid) aqueous solution in gradients at a flow rate of 1.0 mL/min, and a detected wavelength at 245 nm. Relative coefficients of variations of intra-day and inter-day analysis were less than 5% and the relative errors were below 3.9% and 3.7%, respectively. All recoveries were 90.3–119.5%. This method could be applied for the simultaneous determination of the seven marker substances in “Ko-Keng-Tang” and comparisons with commercial preparations.